Conscious experience of time: its significance and interpretation in neuroscience and philosophy
30 September – 2 October 2014
Venue: Berlin School of Mind and Brain, Luisenstraße 56, Festsaal, 10117 Berlin
Organizers: Michał Klincewicz, Sophie Herbst, Anna Strasser
Time is an important dimension of cognition and conscious experience that is still poorly understood. This workshop will provide a forum for serious interdisciplinary collaboration between philosophy and neuroscience, but will appeal to anyone interested in the temporal dimension of conscious experience and perception.
Recent work in philosophy of mind and metaphysics has yielded a number of new theoretical models of the experience of passage of time, duration, and timing of events. At the same time, research in neuroscience has been uncovering the neural mechanisms that underlie time perception and consciousness. This workshop will bridge these common strands in the work of philosophers and neuroscientists. For example, by bringing neurobiological models of temporal perception to bear on theorizing about the content of conscious experience of time and vice versa. We will also discuss subjective distortions of time, which may be useful in testing the viability of such models.
We will also focus on the relationship between world time and subjective time. A collaborative and interdisciplinary dialogue will generate a more comprehensive understanding of the role of time in conscious experience that can bear directly on issues of concern to the public. Among these are explanations of folk psychological metaphors such as ‘time flying when we are having fun,’ but also a better understanding of symptoms of depression, anxiety, Parkinson’s disease, and even ageing, all of which manifest altered sense of subjective time.
Consciousness is structured by time. Everything that exists, from the perspective of subjective experience, occurs now. The past is but a memory, the future, a dream. Nonetheless, everyone not under the spell of an ideology believes in a material universe that has existed for billions of years and will continue to exist for billions more. How can these equally compelling realities be made commensurable? How can time in mind be related to time out of mind?
The beginning of an answer lies in the role time plays in the mind’s capacity to function in its world. Because the environment is in flux, a mind requires some way to track change in order to exploit resources and avoid dangers. Some mechanisms for tracking change are automatic, depending on innate reflexes or associative sequence learning. Conscious time enters when a flexible response is required, and the present situation must be assessed in order to determine the appropriate action. The vast time that stretches from the beginning to the end of the universe does not even occur to a mind until it finds some way to dislodge itself from the present to contemplate its own past and future. Only then can it extend its self-reflection outward to consider the nature of time itself.
Now that our minds have gotten to this advanced state of abstraction, the time is right to consider how we got here, and how a science of the mind can help us understand the neural systems underlying our capacity for temporal perception. I recommend a simple taxonomy for organizing temporal models in relation to 1. unconscious representation, 2. conscious representation, and 3. self-conscious representation.
1. Unconscious representations rely on the automatic mechanisms of sensorimotor systems to track time. It is useful to consider how much work can be done by these systems without invoking consciousness in order to circumscribe the unique work done by conscious time. Unconscious forms of temporal representation are also significant in being directly attuned to environmental change. Perception of diurnal cycles, movement, and duration, as well as sequential learning and structured action depend on timing mechanisms such as neural oscillations and pacemaker-accumulator systems. Neurobiological models primarily involve this sort of time.
2. When different sensorimotor tracking systems need to be coordinated toward flexible pursuit of goals, conscious representations are required. Unconscious temporal mechanisms have the advantage of speed and accuracy in response to defined stimuli. This advantage turns to constraint when the situation calls for an evaluation of present action in relation to future goals. At this point a coordinated representation of the present moment is needed to determine the best response for the particular situation at hand, given a variety of available routes to a chosen goal. The flash-lag illusion demonstrates the way conscious perception integrates sensory representations to facilitate action. In order for motion perception to be effective, a representation should indicate where the moving object is going, not where the light signal originated. Stationary objects do not require an updated spatial position because they can be expected to remain right where they are, at least long enough to be of use. Integrating these competing objectives into a representation of what is happening ‘now’ results in the conscious perception of a spatial dislocation between the moving bar and stationary flash despite their simultaneous presentation at the same location. Research on the timing of perceptual integration, including perception-action integration underlying feelings of agency, applies to conscious time.
3. The point where the mind develops self-conscious representations is also the point where it is capable of forming an autobiographical self, one that is necessary to understanding cultural time, clock time, and world time. At this point events can be marked as having occurred at a specific past time or as planned for some definite future. Because temporal abstraction allows us to become unmoored from the present, all kinds of possibilities and problems arise. We can catalog our history and avoid repeating the mistakes of our predecessors; we can establish a detailed program toward an elaborate project to be completed after our demise. In a darker vein, we might become so obsessed with the passage of time that melancholy prevents actually making use of time; or schizophrenia pulls us into a world with its own disjointed temporal order. While the reassuringly objective standards of clock and calendar suggest that self-conscious time is the most closely calibrated with the world, recent studies of time estimation indicate the opposite. We can slow the passage of self-conscious time by concentrating on our thoughts, or make it fly by disengaging thought entirely. Episodic memory, imagination, and introspection are among the various forms of self-conscious representation that together form a temporally extended self.
As conceptual distinctions in types of temporal perception converge with the tools to measure them, we are uniquely poised to sort out one of the most puzzling aspects of the mind’s relation to its world: does anyone really know what time it is? Put another way, how does the subjective experience of time diverge from, yet remain tied to, objective relations of events?
Passage of time judgements
Passage of time judgements are judgements of the rate at which time seems to pass during some event, rather than judgements of the event’s duration. It might at first seem that these judgements are measures of a person’s direct experience of time passage, thus related to the phenomenology, the basic “feel”, of time, but some research suggests this might not always be the case.
Passage of time judgements can be studied in laboratory settings, via questionnaires asking about time passage in different circumstances (Wearden, O’Donogue, Ogden, & Montogomery, 2014), or by using methods such as Experience Sampling Methodology (ESM: Droit-Volet & Wearden, submitted for publication), with the latter two methods asking questions about time passage in real-life situations.
One question that arises is about the relation between a passage of time judgement and a duration judgement. Suppose we present 2 events A and B, and we require both retrospective duration judgements and passage of time judgements. If event A is associated with a significantly faster passage of time judgement than event B, does it have a longer or shorter duration judgement? Research published in Wearden (2005, 2008) and Wearden et al. (2014) suggests that there is no simple answer to this question. Passage of time judgements can be significantly different in during events A and B, without any significant difference in their duration judgements, suggesting that passage of time judgements and retrospective duration judgements are based on different aspects of the events. In general, changing the “content” of some time period (for example, contrasting an action film with a relaxation video, or manipulating the task carried out in the laboratory) changes passage of time judgements more reliably than duration judgements, although these also sometimes change. However, some situations, such as prospective duration judgements of auditory and visual stimuli, will change duration judgements reliably without any change in passage of time judgements.
Passage of time judgements for real-life events may not always reflect the direct experience of time passage, but may instead be inferences. Wearden et al. (2014) administered a questionnaire which asked about passage of time in different drug and emotional states, and generally found that situations associated with “distraction” from time were associated with faster passage of time, in accord with the idea that “attention to time” is an important determinant of time judgements. However, some results suggested that judgements of “fast” and “slow” time were not mirror-images of one another. “Fast time” anecdotes were analysed and it was found that these invariably involved inferences: “I looked at my watch and it was 3 o’clock therefore time must have passed quickly”. Here, fast time was not experienced, but inferred in retrospect. In contrast, “slow time” anecdotes, occasioned by queues or extreme boredom, seemed to involve the actual feeling of “slow time” during the event itself.
What factors change passage of time judgements in everyday life? Droit-Volet and Wearden (submitted for publication) used ESM to probe local passage of time in elderly and student-age participants, using smartphones which administered 8 probes per day (at quasi-random times) for 5 days. Measures of positive and negative affect, as well as task difficulty and attention, were taken. Higher levels of positive affect were found to increase passage of time judgements only in the younger group, whereas negative affect decreased it in both groups. Likewise, a laboratory study reported in Wearden et al. (2014) suggested that increasingly negative evaluations of a repeated film were associated with slower and slower passage of time judgements in a student group, again suggesting a link between affective variables and judgements of passage of time.
In general, passage of time judgements have been neglected relative to judgements of duration, which is ironic since most “everyday life” statements about time seem to involve them rather than duration judgements. Research by the present author and with colleagues shows that passage of time judgements are not unmeasurable, disorderly, or hard to manipulate in the laboratory, although difficult questions arise about both what the questions used are asking people to report, and how to interpret what they do report.
- Droit-Volet, S., & Wearden, J.H. (submitted for publication). Experience of the passage of time in everyday life in young and older adults: A study using Experience Sampling Methodology. Psychology and Aging.
- Wearden, J.H. (2005). The wrong tree: Time perception and time experience in the elderly. In J. Duncan, L. Phillips, & P. McLeod (Eds.), Measuring the mind: Speed, age, and control (pp. 137-158). Oxford: Oxford University Press.
- Wearden, J.H. (2008). The perception of time: Basic research and some potential links to the study of language. Language Learning, 58, Suppl. 1, 149-171.
- Wearden, J.H., O’Donoghue, A., Ogden, R., & Montgomery, C. (2014). Subjective duration in the laboratory and the world outside. In V. Arstila, & D. Lloyd (Eds.), Subjective time: The philosophy, psychology, and neuroscience of temporality (pp. 287-306). The MIT Press.
Claustrum: From Temporal Integration to Consciousness
Warren H. Meck and Bin Yin
Department of Psychology and Neuroscience
Duke University, Durham, NC USA
Identifying the neural correlates of consciousness has been a difficult task for neuroscientists. In recent years, the claustrum has been proposed to be a possible neural candidate for the coordination of the conscious experience. In this workshop, I will propose that the claustrum plays a crucial role in consciousness by supporting the temporal integration of multisensory patterns of cortical oscillations. This framework for consciousness is based on the striatal beat-frequency model of interval timing (Buhusi & Meck, 2005; Coull, Cheng, & Meck, 2011; Matell & Meck, 2004). Moreover, the proposal that “timing is everything” when it comes to consciousness is based, in part, on the suggestions of Crick and Koch (2005) and Smythies, Edelstein, and Ramachandran (2012) that the claustrum plays a key role in information processing in the brain by correlating the separate neural firings in the different sensory cortices into one coherent activity that “binds” separate sensations into the unitary objects.
Crick and Koch outlined a framework for the scientific study of consciousness (Crick & Koch, 2003). In this framework, the authors proposed that the focus for tackling the “hard problem” of qualia should be finding some neural correlate (s) of consciousness in causal terms, that is, “finding a minimal set of neuronal events that gives rise to a specific aspect of a conscious percept”. They also noted that consciousness is by-and-large “private”, which means that it is impossible to convey one’s conscious experience to another. They focused exclusively on neural activity related to a specific sensory modality, i.e. the visual system of primates, leaving unexplored other aspects of consciousness, such as emotion and self-awareness. While my colleagues and I agree, in principle, with Crick and Koch’s point of view, our goal is to provide a broader framework for consciousness, investigating how inputs from different sensory channels can emerge as a complete picture of our ever-changing conscious experience. As a consequence, any specific sensory percept is construed as one
input to this emergent principle of coalition. In other forums, this has traditionally been referred to as the neural binding problem.
It’s easily overlooked that humans share with other animals a remarkable ability to measure the passage of physical time and “subjectively experience” a sense of time passing (Allman, Teki, Griffiths, & Meck, 2014). It is also tempting to think that to have subjective (conscious) experience it is necessary to perceive the passage of time and understand the concepts of past, present, and future (Allman, Yin, & Meck, 2014), which leads researchers to face the dilemma of whether lower animals have human-like conscious experience. While performing an interval-timing task may not require the total awareness of time passing, more fundamentally our conscious experience may actually be organized by an underlying timing mechanism. Indeed, distinctive from physical entities that have multiple dimensions (at least three dimensions in space and one dimension in time in the classic-physics world), time is arguably the only dimension for mental entities (e.g., thought, feeling, sensory perception, etc.), unless they have other dimensions that could only be measured in a phenomenal world (Smythies, 2003). Therefore, it is intriguing to ask whether our subjective experiences coalesces mainly because we have a built-in timing mechanism that coordinates different channels of inputs that constitutes our
subjective experience. This is particularly important not only because of the hard problem of consciousness that has lingered for centuries, but also because timing and time perception is linked to various types of mental disorders (Allman & Meck, 2012), which can be regarded as “disorders of conscious experience”. One example is schizophrenia, because schizophrenic patients have a distorted sense of reality. Another example is pathological gambling, since pathological gambling can be directly associated with dysfunctional risk assessment and a skewed perception of time and rate of return, which means that gamblers may be ultrasensitive to time and experience a delusional high rate of return in various aspects of their lives. Timing processes provide the fundamental basis for calculating the rate of return for decision-making and the regulation of impulsivity and risk taking. Therefore, disrupted optimization of timing abilities may contribute to their gambling behavior (e.g., Meck, Doyère, & Gruart, 2012; Wittmann, 2013; Wittmann & Paulus, 2008).
First, let’s examine the nature of consciousness. By definition, consciousness refers to one’s individual awareness of one’s unique thoughts, feelings and sensations of the environment. A key characteristic is that these experiences are constantly shifting. The ever-shifting stream of thoughts can change dramatically from one moment to the next, but one’s experience of it seems smooth and effortless. How did the brain produce such stream of conscious experience?
What are the essentials for the emergence of conscious experience? Three possible criteria:
1. The ability to select one state out of the indefinite possibilities (differentiated information) e.g.,
differences between a light sensor and a conscious being.
2. The ability to know that it knows (meta-cognition; second-order representations).
3. The ability to tag personal meaning to the state.
It is important to note that there exist fundamental differences between sensitivity (non-conscious) and awareness (conscious): sensitivity relies on the first-order representation in the system, while awareness relies on the second-order representation for the system. In other words, sensitivity merely entails the ability to respond in specific ways to certain states of affairs, whereas awareness requires the agent to have the knowledge of the fact that he is sensitive to some state of affairs and also cares about certain state of affairs more than others. For example, a camera is not conscious because it is only sensitive to light, but has no awareness of being sensitive to light. One could only make the camera conscious by enabling a second-order learning mechanism that could coordinate its moments of recording light with its memory of past recordings of light, as well as its own preference for that particular moment of light-sensing and memory traces – this mechanism could obviously be the time-keeping mechanism described above. For such a higher-order timing mechanism to work, each channel of inputs must have its own clock(s) so that these clock phases can be synchronized to form a representation of the present –– “now”. The proposal that I will introduce at the Berlin workshop is that the claustrum is critical for the type of temporal integration required by consciousness.
Allman, M.J., & Meck, W.H. (2012). Pathophysiological distortions in time perception and timed performance. Brain, 135, 656-677.
Allman, M.J., Teki, S. Griffiths, T.D., & Meck, W.H. (2014). Properties of the internal clock: First- and secondorder principles of subjective time. Annual Review of Psychology, 65, 743-771.
Allman, M.J., Yin, B., & Meck, W.H. (2014). Time in the psychopathological mind. In D. Lloyd & V. Arstila (Eds.), Subjective time: The philosophy, psychology, and neuroscience of temporality, pp. 637-654, Cambridge, MA: MIT Press.
Buhusi, C.V., & Meck, W.H. (2005). What makes us tick? Functional and neural mechanisms of interval timing. Nature Reviews Neuroscience, 6, 755-765.
Coull, J.T., Cheng, R.K., & Meck, W.H. (2011). Neuroanatomical and neurochemical substrates of timing. Neuropsychopharmacology Reviews, 36, 3-25.
Crick, F.C., & Koch, C. (2003). A framework for consciousness. Nature Neuroscience, 6, 119-126.
Crick, F.C., & Koch, C. (2005). What is the function of the claustrum? Philosophical Transactions of The Royal Society B, 360, 1271-1279.
Matell, M.S., & Meck, W.H. (2004). Cortico-striatal circuits and interval timing: Coincidence-detection of oscillatory processes. Cognitive Brain Research, 21, 139-170.
Meck, W.H., Doyère, V., & Gruart, A. (2012). Interval timing and time-based decision making. Frontiers in Integrative Neuroscience, 6:13.
Merchant, H., Harrington, D.L., & Meck, W.H. (2013). Neural basis of the perception and estimation of time. Annual Review of Neuroscience, 36, 313-336.
Smythies, J. (2003). Space, time and consciousness. Journal of Consciousness Studies, 10, 47-56.
Smythies, J., Edelstein, L., & Ramachandran, V. (2012). Hypotheses relation to the function of the claustrum. Frontiers in Integrative Neuroscience, 6:53.
Wittmann, M. (2013). The inner sense of time: How the brain creates a representation of duration. Nature Reviews Neuroscience, 14, 217-223.
Wittmann, M., & Paulus, M.P. (2008). Decision making, impulsivity and time perception. Trends in Cognitive Sciences, 12, 7-12.
The “consciousness boom” that began in the last decade of the last century shows no sign of ending nearly a quarter of a century on. One consequence of the boom has been a renewal of interest in long-ignored (by analytically inclined philosophers) metaphysical options regarding the relationship between consciousness and the rest of reality: panpsychism and dualism are now being taken seriously in a way that would have been almost unthinkable a quarter of a century ago. Another consequence has been a renewal of interest in phenomenological questions. In recent years there has been a lot of new interest in two areas in particular: cognitive phenomenology (so-called), and temporal experience, which will be my focus here.
I will briefly outline the main issues which have been dividing opinion among philosophers working on time-consciousness over the past five years or so, and provoked the most argument. One issue concerns whether there is anything that is distinctively temporal about experience at all. Philosophers who believe we directly experience change and persistence think that there is; philosophers who deny that we experience such phenomena think there isn’t. Philosophers in the first camp agree that we experience temporally extended phenomena (or seem to), but the disagree – quite radically – about how this is possible. According to one view, which can be traced back to Brentano and Husserl, the experience of change takes place in momentary (or near-momentary) conscious states. According to a competing view, which can be traced back to William Stern, change-experience takes place in experiences which are themselves extended in time. These competing views are also associated with very different accounts of the structure our streams of consciousness possess over longer periods of time.
Much of the empirical work on carried out in neuroscience and psychology has focused on quite different issues. How do our brains manage to keep track of time, by measuring or estimating temporal intervals over minutes, hours or days? Several quite different “internal clock” mechanisms have been proposed. A great deal of work has been carried out on our abilities to compare and judge the length (duration) of intervals. Interesting as they are, questions such as these are (not obviously) of direct relevance to the philosophical debates concerning the character and structure of our experience from moment to moment. This does not mean that recent philosophical debates have been entirely uninfluenced by scientific findings, or carried out in isolation from them - there are several ways in which the philosophical debates have been influenced by empirical findings. That said, there is plenty scope for scientific work to have far greater influence on the philosophical debates than they have had so far, but only if the right questions are addressed.
Issues concerning the fine-structure of consciousness can easily seem quite esoteric – and so comparatively inconsequential. In fact, the opposite is the case: a good deal hangs on them. The time-consciousness debate is relevant to some central questions concerning nature of the self (or at least, when the self construed as a subject of experience). These issues also impact significantly on metaphysical and cosmological controversies concerning the nature of time itself. The character of temporal experience is also some surprising epistemological ramifications. To mention but one, the different accounts of time-consciousness have very different implications with regard to the likelihood of our being “Boltzmann brains”.
Sylvie Droit-Volet: Subjective Experience of Time In Human Beings
High abilities of timing and time perception have been observed in animals of different species and humans at different levels of the ontogenetic scale. In addition, animals and humans exhibit the same scalar properties of time, with accurate temporal estimates in mean and a variability increasing with the length of durations to be estimated. Researchers have thus assumed that humans and animals share in common the same sense of time, and try to find the mechanisms (internal clock) in the brain underlying this sense of time. However, in humans, the judgment of time cannot be reduced to a by-product of a physiological internal clock mechanism. Indeed, human adults are aware of passage of time. They know that they are subjects of temporal illusions, that their experience of passage of time changes as a function of their emotional states or their activities when they capture attention. They express for example their awareness of a slowing down or an acceleration of passage of time when they are sad and happy, respectively. The question is: what is the role of humans’ consciousness of passage of time on their temporal judgments? Does awareness of passage of time involve cognitive processes that are completely independent of processes involved in the perception of time? Several studies will be presented allowing us to try to respond to these important questions.
Yvonne Förster-Beuthan: Time-Consciousness and Embodiment
The phenomenon of distortions of time-consciousness immediately raises the old question of the ideality of time. If the perception of time can be distorted it seems to follow that time is a mental and hence ideal form.In my talk I want shed some light on the idea that time-consciousness is as embodied as motion perception or colour perception. Just as in the case of colourperception the perception of time seems to have exact correlate in the physical world. In the case of colour there are physical properties of surfaces that cause our specific visual senses to perceive those surfaces as endowed with a certain shade of colour. The colours themselves do not seem to be „out there“. With time it gets even shadier. Which physical qualities could be the cause of our temporal perception. It is hard to say. But left aside the questions of relativity or even quantum physics there still is the conviction that perception of time has its causes not only „in our heads“. The temporal characteristics of movement, day and night rhythms, the sounds of dropping water: the environment has features that can be experienced as temporal in contact with an embodied cognitive system.If the concept of embodiement can account for colour perception in the sense that colours are perceived by means of a specific body and ist being embedded in a certain environment, then it is not that farfetched to account for time-perception in a similar way. The question I am going to ask is: Does the body play an yet to be specified role in the perception of time and what are the features in the world it is responding to. To take my inquieries one step further I would like to start an open reasoning on how distortion of time-consciousness might also be accounted for in terms of an embodied approach.
Dan Zakay: Subjective duration: a measure reflecting cognitive entropy
Entropy is the amount of disorder in a closed system. According to the second law of thermodynamics the amount of entropy in a closed system can only increase with time. Because of this, the direction of the " time arrow" can be inferred from the direction of the increase in entropy. In order to reverse the direction of entropy, the system must be open and outside energy must be invested in the system. This is the case in biological systems in which the creation of an organism implies a decrease in the level of entropy. This is possible because of the supply of energy in the form of food, water, oxygen, etc. to the organism. When an organism dies, entropy increases again, with time.Cognitive entropy can be defined as the amount of disorder in mental activity. Thinking analytically requires investing energy in the thinking system; i.e., the brain. The brain uses up almost 20% of the energy consumed by the whole body, although its weight accounts for only 2% of total body weight. Cognitive disorder or entropy is manifested by disordered thoughts, cognitive errors, illusions and delusions. This is the case for several mental illnesses in which mental activity is impaired such as in schizophrenia. While it is difficult to measure the amount of cognitive disorder in such states, cognitive entropy can be observed as well in normal individuals when they do not invest much energy in their thinking processes. In such cases people might feel bored, or will exhibit low Intensity of thinking as is the case when system 1 is used. Decisions will be based on habits, intuition and heuristic thinking that result in errors and cognitive biases. In such cases, prospective duration judgment can serve as a measure of the amount of cognitive entropy. According to attentional models of prospective duration judgment such as the Attentional-Gate-Model (AGM), prospective duration is a function of the amount of attentional resources allocated for timing in a given situation. Attentional resources are scarce and hence there is an ongoing competition for attentional resources. When individuals are asked to prospectively judge the duration of a concurrent non-temporal task, attention needs to be divided between the task and the timing. The more demanding a task, the more attentional resources are allocated for its performance and fewer attentional resources remain available for timing. The outcome is a shortening of duration judgment. This differs from a situation in which a person is asked to prospectively judge the duration of a routine task, which does not demand many attentional resources. In this case duration will be felt to increase. Thus for normal cognitive systems the feeling that the duration is becoming longer reflects an increase in cognitive entropy and vice versa. The symbolic meaning is that when we feel the passage of time we are, most probably, engaged in low level cognitive and information processing. In the opposite case, we do not feel the passage of time. The difference between the length of felt duration of same intervals in which different levels of cognitive and information processing load are required, can serve as a measure of cognitive entropy.
Christoph Hoerl: Time and the Domain of Consciousness
The way in which we experience time is often said to conflict with what metaphysics or physics tell us about time, which would imply that our experience of time is, in an important respect, illusory. In this talk, I explore the extent to which this can really be the case. If time as we experience it is different from what time is actually like, our experience of time must involve some kind of construction, apparently presenting us with a feature of time that time does not actually have. Yet, on reflection, it is not obvious that we can make sense of the idea that our experience of time could involve a construction in this sense. I suggest that what may appear like a conflict between our experience of time and the nature of time itself actually has to do with the fact that there are quite different ways - structurally different ways - in which we can become aware of how things unfold over time, which we don't always distinguish clearly enough from one another.